Sminthurides parvulus is generally blue in colour and is common and widespread. Males reach 0.3 mm in length whereas females grow to 0.5 mm.
In Sminthuridesspecies, the male antenna is modified to grasp the female during mating and the long spine on the second antennal segment (ant2) is curved (Fig. 1). Females do not possess sub-anal appendages (SAA). In Sminthurides parvulus, the fourth antennal segment in the female is divided into five subsegments (Fig. 2). The mucro does not bear lamellae and is 'gutter'-shaped (Figs. 3, 4). A tibiotarsal organ (tt organ) is present on the third leg (Fig. 5) and the empodium of the foot has a long filament that reaches well beyond the tip of the claw (Figs. 6).
Most records forSminthurides parvulus are from wet moss.